1. Technical Field
The present invention relates to techniques for executing processing in each storage area on an individual bases.
2. Related Art
Various schemes have been proposed for managing functions or services provided to users on a user-by-user or group-by-group basis. For example, according to techniques disclosed in JP-A-2001-312474, in order to prevent leakage of information that is managed on a user-by-user basis to an unauthorized third party, for each device on a network, a user allowed to use the device is defined in advance so that only the user is allowed to use the device or to use a certain function of the device.
Recently, flash memories called USB (Universal Serial Bus) memories are commonly available. A USB memory can be connected to or disconnected from a host apparatus having a USB port. By connecting a USB memory to a USB port of a host apparatus, a user of the host apparatus can execute various types of processing, such as reading or deleting data stored in the USB memory or writing data to the USB memory. Since USB memories are portable, a single USB memory can be shared by a plurality of users. In that case, data of one user, stored on the USB memory, could be browsed or tampered with by other users.